In this Phase 1 proposal, Forkhead BioTherapeutics Inc. (Forkhead Bio) aims to demonstrate target validation that selective Foxo1 inhibitors reprogram gut cells into glucose-responsive insulin-producing (?-like) cells in vitro and in vivo, use a recently established robust assay platform to drive compound optimization, and identify one or more lead molecules with attractive profiles suitable for additional proof-of-concept studies. Our preliminary data strongly suggest that we?re well positioned to complete the proposed work within the funding period and provide key feasibility data to show that chemical inhibitors of Foxo1 can leverage the body?s potential for conversion of gut cells into ?-like cells to cure type 1 and treat type 2 diabetes. Over 12 million patients with type 1 diabetes or late stage type 2 diabetes in the US and EU require life- long insulin injections. Under current treatment paradigm, over 50% of patients with diabetes fail to meet clinical goals of blood glucose management. This is largely due to the narrow therapeutic window and life- threatening potential of hypoglycemia of all insulins in clinical use. Therefore, developing therapies that restore or mimic endogenous pancreatic ? cell function, namely, releasing insulin in a glucose-regulated manner, remains the holy grail for diabetes research. Forkhead Bio?s co-founder Dr. Domenico Accili and colleagues made the groundbreaking discovery that ablation of Forkhead box protein O1 (Foxo1), a transcription factor, in the gastrointestinal tract leads to reprogramming of a subpopulation of enteroendocrine cells into insulin- positive cells in mice and in cultured human gut organoids. The reprogrammed gut cells release insulin only when ambient glucose is high and can restore normal glucose metabolism in a mouse model of insulin- deficient diabetes. These findings raise the possibility of an innovative approach by which specific enteroendocrine cells can be converted into ?-like cells by inhibiting Foxo1, so that the gut takes over insulin production from the failing pancreatic ? cells in diabetes. Work by Accili et al. also uncovered several series of small-molecule chemicals that specifically inhibit Foxo1, providing evidence that developing an oral therapy for this target is possible. These data collectively suggest that this approach has the potential to produce a transformative oral therapy that would radically reduce or even eliminate the need for insulin injections and the burden of frequent blood glucose monitoring through finger pricks, thereby significantly improving clinical outcomes and quality of life for patients with diabetes, while substantially reducing medical costs. Forkhead Bio, recently co-founded by Dr. Accili (Director, Chair of Scientific Advisory Board), Charles Queenan (Director, CEO), and Dr. Hua Lin (CSO), has established strategic collaborations with investigators at the Naomi Berrie Diabetes Center and the Organic Chemistry Collaborative Center at Columbia University. If awarded, work under this SBIR will complement and boost these efforts and substantially accelerate the translation of this promising innovation into an efficacious and patient-friendly therapy.